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《Comptes Rendus Chimie》2007,10(3):152-177
Over the last years, interest involving ionic liquids (ILs) used as reaction medium for homogeneous enantioselective catalysis has exponentially expanded. In many cases, the use of ILs provides several advantages over reactions in organic solvents in terms of activity and enantioselectivity. Even more important, the catalyst immobilization in IL can avoid its leaching and consequently favour its recycling. This review deals with recent advances in the investigation of these new solvents in asymmetric catalysis. We go over enzymes, chiral organocatalysts and metal complexes containing chiral ligands used in enantioselective processes using ionic liquids, with special emphasis on the catalyst reuse and also the separation of organic products. 相似文献
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Bala Subramaniam 《Coordination chemistry reviews》2010,254(15-16):1843-1853
Employing a multiscale systems-based research approach, chemists and chemical engineers at the Center for Environmentally Beneficial Catalysis (CEBC) are collaboratively addressing major grand challenges facing the sustainable manufacture of fuels and chemicals from both traditional and renewable feedstocks. By judiciously combining the principles of green chemistry and green reactor engineering, augmented by valuable insights from industrial partners, CEBC researchers are developing alternative technology concepts that minimize the environmental footprint of chemical manufacturing processes including the reduction of carbon emissions. Such collaborations have resulted in several remarkable discoveries as follows: CO2-expanded liquids (CXLs) as reaction media for selective and inherently safe O2 oxidations including that for terephthalic acid production from p-xylene with potentially reduced solvent burning (i.e., reduced carbon footprint); propylene oxide production with environmentally benign solvents and oxidant, exploiting the compressibility of propylene at ambient temperatures for process intensification; a novel pressure-intensified ethylene oxide process virtually eliminating CO2 formation as a byproduct; highly selective hydroformylation of higher olefins employing CXLs and soluble polymer-supported homogeneous Rh-based catalysts that are easily retained in solution while the product is isolated by membrane filtration; and creation of nanoparticles of transition metal complexes with unique functional properties such as reversible oxygen binding and room-temperature nitric oxide disproportionation. Quantitative economic and environmental impact analyses have been employed to benchmark CEBC's novel technology concepts against conventional processes and to guide research and development. Examples of such advances in green processing are discussed in this review. 相似文献
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Kexin Liu Zhuyi Wang Liyi Shi Siriporn Jungsuttiwong Shuai Yuan 《Journal of Energy Chemistry》2021,(8):320-333
The pursuit of high energy density has promoted the development of high-performance lithium metal batteries.However,it faces a serious security problem.Ionic li... 相似文献
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Zhang P Gong Y Lv Y Guo Y Wang Y Wang C Li H 《Chemical communications (Cambridge, England)》2012,48(17):2334-2336
A series of stable (air, water stable and with good thermal stability) and hydrophobic ionic liquids based upon metal chelate anions were synthesized, which were shown to be effective, mild, and easy to recycle catalysts at the same time stable solvents for the oxidation of cyclohexene. 相似文献
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Ionic liquids in enzymatic catalysis and biochemical methods of analysis: Capabilities and prospects
S. V. Muginova A. Z. Galimova A. E. Polyakov T. N. Shekhovtsova 《Journal of Analytical Chemistry》2010,65(4):331-351
The first Russian review systematizes and discusses the most important and promising published data on the use of ionic liquids
in biocatalysis and, especially, biochemical methods of analysis. Studies on the use of ionic liquids as solvents for enzymes,
new reaction media for enzymatic reactions, and components of the biosensitive layers of sensors are analyzed. The physical
and chemical properties of ionic liquids used in biocatalysis are discussed. The advantages of ionic liquids over the usual
solvents in homogeneous and heterogeneous reactions with the participation of enzymes from various classes are demonstrated,
procedures for the coimmobilization of biocatalysts and ionic liquids with cellulose onto polymer supports and electrodes
are described, and prospects for the use of enzyme-ionic liquid compositions in biochemical methods of analysis are considered. 相似文献
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This short review is focused on recent findings on the role of ionic liquids (ILs) in catalysing the hydrogenation of levulinic acid (LA) to gamma valerolactone (GVL), which is a cascade reaction involving more than one type of reaction. A brief introduction on green aspects of IL as a catalyst followed by various types of ILs being used for hydrogenation of LA to GVL are discussed. The unique characteristics of ILs responsible for hydrogenation reaction are also explained along with the current and upcoming scenario of IL catalysed hydrogenation of LA to GVL. 相似文献
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Salicylaldoxime and salen containing imidazolium ionic liquids for biphasic catalysis and metal extractions 总被引:1,自引:0,他引:1
Naik PU McManus GJ Zaworotko MJ Singer RD 《Dalton transactions (Cambridge, England : 2003)》2008,(36):4834-4836
Imidazolium salts containing salicylaldoxime or salen ligands readily form ionic metal complexes with copper and manganese; hence offering applications in metal extractions and biphasic catalysis. 相似文献
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Satoshi Kitaoka 《Tetrahedron》2005,61(32):7678-7685
In place of widely used dichloromethane, a series of ionic liquids, ILs, was employed as a reaction medium for the one-flask preparation of tetraarylporphyrins. The porphyrin yield in the IL was comparable to that in the dichloromethane, as long as both the water content and the fluidity were conditioned to be in the optimum state. When acidic IL, [C4-SAbim][CF3SO3] possessing a sulfonic acid moiety was used as the reaction medium, nothing but a black tarry by-product was obtained due to its strong acidity. However, using the acidic IL in a biphasic mode together with dichloromethane enabled porphyrins to form, even at a high reactant concentration. Furthermore, the phase-separated acidic IL was reusable for at least 10 times without any loss of catalytic activity. 相似文献
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The synthesis of ionic liquids based upon functionalized quaternary ammonium salts and metal salts of zinc, tin, or iron is demonstrated. The freezing point of these ionic liquids was studied as a function of the quaternary ammonium cation. The complex anions were identified and quantified using mass spectrometry and potentiometry. It is shown that the primary zinc anion is Zn(2)Cl(5)(-) with Zn(3)Cl(7)(-) becoming more abundant in more Lewis basic solutions. Similar results were observed for ionic liquids containing SnCl(2). The surface tension was also measured and was used to explain the high viscosity of the ionic liquids in terms of the large ion:hole size ratio and the small probability of finding a hole of suitable dimensions adjacent to a given ion to permit movement. The phase behavior of a variety of quaternary ammonium halides/ZnCl(2) mixtures is characterized and it is shown that the depression of freezing point is related to the increase in size of the component ions. 相似文献
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N. A. Smirnova E. A. Safonova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2010,84(10):1695-1704
Problems of self-assembling in systems containing ionic liquids (ILs) are discussed. Main attention is paid to micellization
in aqueous solutions of dialkylimidazolium ILs and their mixtures with classical surfactants. Literature data are reviewed,
the results obtained by the authors and co-workers are presented. Thermodynamic aspects of the studies and problems of molecular-thermodynamic
modeling receive special emphasis. It is shown that the aggregation behavior of dialkylimidazolium ILs is close to that of
alkyltrimethylammonium salts (cationic surfactants) though ILs have a higher ability to self-organize, especially as it concerns
long-range ordering. Some aspects of ILs applications are outlined where their common features with classical surfactants
and definite specificity are of value. 相似文献
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《Journal of Energy Chemistry》2016,(2)
The performance of an electrocatalyst, which is needed e.g. for key energy conversion reactions such as hydrogen evolution, oxygen reduction or CO2 reduction, is determined not only by the inherent structure of active sites but also by the properties of the interfacial structures at catalytic surfaces. Ionic liquids(ILs), as a unique class of metal salts with melting point below 100 ℃, present themselves as ideal modulators for manipulations of the interfacial structures. Due to their excellent properties such as good chemical stability, high ionic conductivity, wide electrochemical windows and tunable solvent properties the performance of electrocatalysts can be substantially improved through ILs. In the current minireview, we highlight the critical role of the IL phase at the microenvironments created by the IL, the liquid electrolyte, catalytic nanoparticles and/or support materials, by detailing the promotional effect of IL in electrocatalysis as reaction media, binders, and surface modifiers. Updated exemplary applications of IL in electrocatalysis are given and moreover, the latest developments of IL modified electrocatalysts following the "Solid Catalyst with Ionic Liquid Layer(SCILL)" concept are presented. 相似文献
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Ionic liquids (ILs) are being increasingly studied in many different chemical application areas, particularly in green solvent applications that are extending into microemulsion applications. We summarize herein these initial microemulsion formulations and applications where ILs are used as oil substitutes, water substitutes, co-surfactants (additives), and surfactants. 相似文献
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Ionic liquids as media for nucleophilic fluorination 总被引:1,自引:0,他引:1
The use of Room Temperature Ionic Liquids (RTILs) for a variety of halogen exchange (Halex) fluorination processes using alkali metal fluorides is assessed. Whilst fluorination of a range of halogenated substrates is possible in good yield, the utility of RTILs as reusable, inert media for such reactions is limited by the gradual decomposition of the RTIL in the presence of highly basic fluoride ion. 相似文献
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In the field of green chemistry, micellar catalysis plays a central role for organic solvent replacement. Micelles ensure the solubilization or dispersion of catalyst and organic substrates in water imparting unique features in terms of chemo-, regio- and stereoselectivity. For metal-catalyzed reactions, a more robust approach for catalyst recycling consists in the synthesis of so-called metallosurfactants, in which a hydrophilic metal–containing headgroup is endowed with a hydrophobic ponytail, leading in water to the formation of metallomicelles. This fast-growing field of research is critically reviewed in this contribution, describing new trends and classifying the literature since 2017 based on the nature of the newly formed bond. Particular emphasis is reported on the specific features of metallosurfactants in terms of activities, selectivities and recyclability of the self-assembling catalysts. 相似文献
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对价格昂贵的手性催化剂进行回收和重复利用是目前不对称催化领域面临的难题之一,受到学术界和工业界的共同关注。化学家们已经尝试了许多方法,其中使用离子液体来替代常规有机溶剂使催化剂得到分离和重新使用已经引起他们极大的兴趣。本文综述了近年来在离子液体中进行不对称催化反应的研究进展,对离子液体中过渡金属和有机小分子催化的各种反应进行重点介绍,强调了离子液体不但在催化剂回收方面有独特优势,而且在许多反应中能够提高催化效率。 相似文献